Method of establishing a fluid-tight closure



Aug. 16, 1960 w. H. Bowl-:s 2,948,959

METHOD oF ESTABLISHING A FLUID-TIGHT cLosURE Filed May s, 1958 s sheets-sheet 1 I\ N w n N Q Q l ll.

@of I' i Aug. 16, 1960 w. H. BOWES 2,948,959

METHOD 0F ESTABLISHING A'FLUID-TIGHT CLosURE Filed May 6, 1958 3 Sheets-Sheet 2 Aug. 1s, 1960l METHOD OF ESTABLISHING A FLUID-TIGHT CLOSURE Filed May 6, 1958 v 5 Sheets-Sheet 3 my@ y United States Patent O METHOD OF ESTABLISHING A FLUID-TIGHT CLOSURE William H. Bowes, Peterborough, Ontario, Canada, as-

signor to Atomic Energy of Cana'da Limited, Ottawa, Ontario, Canada This invention relates to a method of establishing a duid-tight closure, and has for its object the provision of ya closure for `a tubular member. The term tubular member is chosen for convenience of description but is not intended to imply that the invention is restricted to use with a member of circular cross-section, the invention being lapplicable to any annularly shaped member whatever itsshape in cross-section. Similarly it is not the intention that tubular member should imply an elongated tubular vessel; the tubular member may be short, and may comprise merely a protuberance on a vessel of any shape.

For the purpose of the invention, there is provided a closure Iassembly for the tubular member, such assembly comprising an annular seating surface formed on the tubular member, a flexible sealing disc mounted with a sealing area of the inner face thereof in register with such annular seating surface for pressure sealing engagement therewith, a plug for engagement with the tubular member, bearing surfaces projecting from the inner end of the plug positioned for engagement with areas of the outer face of the disc radially intermediate the centre thereof and said sealing area, and disc-controlling means for deflecting inwardly the centre of the disc to force the sealing area thereof against said seating stu-face, such means extending from the exterior of the assembly to the central area of the disc whereby to be operable from the exterior of the Iassembly.

The method according to the invention consists of initially partially assembling the parts by introducing the plug into the tubular member sutiiciently to bring the sealing area of the disc at least approximately into substantially pressureless contact with the seating surface, acting on the disc-controlling means to force the centre of the disc inwardly and urge its sealing area into pressure engagement with the seating surface, then moving the plug further into the tubular member to bring its bearing surfaces into pressure engagement with said intermediate areas of the disc, and inally releasing :the disccontrolling means.

The manner of carrying the invention into practice is illustrated, by way of example, by the structures shown in the accompanying drawings, in which:

'Figure 1 is a central section showing .a closure assembly in partially closed condition;

lFigure 2 is a view similar to Figure 1 showing the parts at a later stage in carrying out the closing operation;

Figure 3 is a further similar view at a still later stage in this operation;

Figure 4 is another view of the same parts with the assembly in the fully .closed position; and

Figure 5 is a view of an alternative construction, showing `the parts in a position corresponding to that of Figure 1 of the rst construction.

Referring iirstly to 'Figure l, this view shows a tubular member an open end of which is to be provided with a duid-tight closure. For this purpose, the member 10 is provided with an internal thread 11 constructed for Patented Aug. 16, 1960 engagement with external threads 12 formed on a plug 13 adapted to engage and form the main physical structure, but not the fluid-tight aspect, of the closure.

Alternatively, instead of providing a threaded engagement between the plug and the tubular member, the plug could slide into the tubular member and be held Itherein by suitable means such yas a transversely extending wedge passing through the tubular member and through a ltransverse passageway in the plug. This method of retaining the plug is especially suitable when the cross-section of tubular member and plug is noncircular (say elliptical) and the plug thus cannot be rotated 'in vthe tubular member.

At its inner end, the plug 13 is formed with an annular projection 14 which provides bearing surfaces acting against therear of a flexible circular disc 15 which is supported within .an annular flange .16 projecting from the inner end ofthe plug 13'. lt is not essential that a single annular projection 14 be employed. A series of annularly Idisposed discrete projections could be employed, instead, to provide the necessary bearing surfaces. A circular gasket 17 extends acoss the inner face of the exible disc 15 and around the annular flange 16 into an .annular cavity 18 formed between the tubular member 10 and the plug 13. The tubular member 10 is formed with .an annular seating surface 19 positioned for `engagement by the outer peripheral sealing area 26 of the disc 15 (with the sealing gasket 17 interposed). The surface 19 is preferabably of circular form', but can follow any other annular shape .that may be adopted for the tubular member.

A turning bar 24 is formed on the outer end of the plug 1'3 for rotating the same.

Within a central hole 20` extending through the plug 13 and turning bar 24 there is slidably mounted .a push rod Z1 which terminates at its inner end in a bearing surface 22 and at its outer end in an operating surface 23.

Figure l shows the parts assembled but with the assembly brought only to the partially closed position, i.e. with the sealing area 26 of the disc 15 approximately in gently, i.e. substantially pressureless contact (through gasket 17) with the seating surface 19.

To move the parts to the fully closed position, a predetermined axial force is firstly applied from the exterior to the push rod 21, thereby forcing inwardly the centre of the iiexible disc 15 and arching the same in a manner shown in Figure 2 and establishing pressure contact between sealing area 26 and seating surface 19. With the push rod 21 and hence the disc 15 held in this position the plug .16 is rotated by the bar 2.4 to bring the bearing projection 14 firmly up against the rear of the disc 15, the projection 14 bearing against an annular area 27 of the disc 15 that is radially intermediate the centre of the disc and the sealing area 2,6. This is the position shown in Figure 3. By operating in this manner there is no relative rotation between the sealing area 26 of .the disc 15 and the seating surface 19, which parts form the huid-tight seal, or between these parts and the interposed gasket 17, during a time when the parts are in pressure contact with one another.

Finally, the push rod 21 is released, as shown in Figure 4, to allow the disc 15 to move back. The remaining `deflection in such disc is shown in somewhat exaggerated form in AFigure 4 for clarity of illustration. In fact, all the drawings exaggerate the deilections from those normally experienced in practice, otherwise clear illustration would not result.

When the parts take up this nal position, the disc 15 is still stressed, with the result that it exerts a substantial sealing pressure through its sealing area 26 on the seating surface 19, the projection 14 acting as a fulcrum. 4Fuid pressure .can then be introducedr intoA the interior yof the member 10, and such internal pressure will tend to increase the sealing pressure between the area 26 and the seating surface 19, the annular projection y14- continuing yto act as a. fulcrum for vthis action. n

Demounting of the assembly is carried out by a simple reversal of the `closing steps described above.

In the alternative construction shown in Figure 5, the push rod 21 is rigidly `connected to the flexible disc 15 and serves to support it. In this case an annular gasket 25 is used to replace .the circular gasket 17.A In other respects the structure and manner of operation of thisdevice is similar to that of the embodiment already described.

I claim:

A method of` establishing a fluid-tight closure in an assembly comprising a tubular member, an annular seating surface formed on said member, a exible sealing disc mounted with a sealing area of the inner face thereof in register with said annular seating surface for pressure sealing engagement therewith, a plug for engagement with said tubular member, 'bearingY surfaces projecting from the inner endY of said plug positioned for engagement with areas of the outer face of said disc radially intermediate the centre thereof and said sealing area, and disc-controlling means for deliecting inwardly the centre of said disc to yforce the sealing area thereof Aagainst said seating surface, said means extending from the eX-terior of the assembly to the central area of said disc whereby to be operable from the exterior of the assembly; .said method comprising initially partially assembling the parts by introducing the plug into the tubular member suliciently `to bring said sealingl area of the `disc at least approximately into substantially pressureless contactV with said seating surface, acting on said disc-controlling means to iieX the centre'of the `disc inwardly and urge its sealing area into engagement with said seating surface to increase the pressure between said sealing areaA andsaid seating surface, ythen moving said plug further into said tubular member .to bring said bearing surfaces on said plug into pressure engagement 'with said intermediate areas of saiddisc, and finally releasing said disc-controlling means.

References Cited in the file of'this patent UNITED STATES PATENTS 1,372,246 Putnam Mal'. 2.2, 1921 1,939,553 Hill Dec. 12, 1933 2,656,592 Cataldo Oct. 27, 1953 

